1. Field of the Invention
The present invention generally relates to an accelerator reaction force control apparatus for controlling an operating force of an accelerator of a vehicle.
2. Background Information
An accelerator reaction force control apparatus have been proposed for controlling an operating force (depression reaction force) of an accelerator pedal of a vehicle. An example of such an accelerator pedal reaction force control apparatus is disclosed in Japanese Laid-Open Patent Publication No. 2003-120339. This publication discloses controlling the engine by switching between a first operating method (e.g., homogeneous combustion) used in a high rotational speed/high load region and a second operating method (e.g., stratified combustion) used in a low rotational speed/low load region for a higher fuel efficiency than the first operating method. When an engine operating region changes from a second operating region where the second operating method is used to a first operating region where the first operating method is used, the depression reaction force (reaction force of the accelerator pedal) is suddenly increased at a boundary operating region occurring immediately before the first operating region is entered. Meanwhile, the increase of the reaction force is cancelled when the operating region returns to the second operating region from the boundary operating region.